There are many instances in which it is necessary or desirable to apply a coating, plating or layer of silver or a silver-containing compound to a substrate. Examples of such applications would include electrode plating for switches such as those used on pressure-sensitive switches or control panels, for example, as are used on appliances such as microwave ovens, conventional ovens, and the like. Such silver plating also is commonly used in the semiconductor fabrication arts to apply silver metalizations on silicon or germanium semiconductor wafers. Other examples of such substrates include, without limitation, such things as polyesters, polycarbonates, vinyls, ceramics, glass, and the like.
The predominant approach heretofore used in applying silver to substrates has involved using a solvent-based silver solution to the substrate, and chemically or thermally curing the solution to evaporate the solvent. This leaves the solid silver plating on the substrate.
This conventional approach is disadvantageous in a number of respects. Of perhaps the greatest concern is the fact that the solvents currently used for this purpose are toxic. They require special handling and disposal facilities and techniques, and correspondingly increase inefficiencies and costs. Even while observing these special handling techniques, they present hazards to workers using these toxic materials. The solvent-based compositions and methods also are disadvantageous in that it can be difficult to predict the uniformity and thickness of the resultant silver plating after the solvent has evaporated. This leads to quality and performance variations.